Apparatus for the thermic treatment of metal wires, filaments, bands, or the like



Jan. 8, 1935. K. MOERS APPARATUS FOR THE THERMIC TREATMENT OF METAL WIRES, FILAMENTS, BANDS, OR THE} LIKE 2 Sheets-Sheet 1 Filed Nov. 22, 1952 Inventor! Kurt Moers,

by MW,

His Attorney.

Patented Jan. 8, 1935 PATENT OFFICE- APPARATUS FOR THE THERMIC TREAT- MENT F METAL WIRES, FILAMENTS, BANDS, OR THE LIKE Kiirt Moers, Berlin, Germany, assignor to General Electric Company, a corporation oi New York Application November 22, 1932, Serial No. 643,890 In November 25, 1931 10 Claims.

My invention relates to improvements in apparatus for the thermic treatment of metal wires, filaments, bands, or the like, and more particularly in apparatus comprising a container provided with openings for passing thesaid elongated member therethrough, the said openings being provided with sealing means for closing the container to the outer air. In apparatus of this class such as are now in use'the said openings take the form of tubular extensions of the container comprising seals of mercury, and such apparatus are satisfactory for treating the wires within the container under atmospheric pressure. But in some cases, for example 'when it is desired to glow wires or the like of oxidizable metal such as tungsten or tantalum, or to precipitate on metal wires a metal such as zirconium from an atmosphere of zirconium tetra iodide, the seal must be constructed so that the sealing medium is not forced by differential pressure into the'container. The object of the improvements is to provide an apparatus in which the wire or the like is passed into the container in a tight manher, and in which means are provided for preventing the sealing medium from being forced into the container by differential pressure. With this object in view my invention consists in providing one or more chambers in connection with the tubular extensions and the seals thereof in which a pressure is maintained which is equal to or but slightly higher than the pressure within the container, so that the differential pressure acting on the sealing medium from the side of the container and the said chamber is not able to force the sealing medium into the container.

For the purpose of explaining the invention several examples embodying the same have been shown in the accompanying drawings in which the same reference characters have been used in 40 all the views to indicate corresponding parts. In

said drawings,

Fig. 1 is an elevation partly in section showing the apparatus,

Fig. 2 is a fragmentary elevation partly in section illustrating a modification of the apparatus and showing one end thereof, and

Fig. 3 is an elevation similar to the one illustrated in Fig. 1 and showing another modification.

In the example shown in Fig. 1 the apparatus is designed for coating a wire or similar elongated member with a metal which is precipitated from a vapour of a compound containing the sa'idmetal. As shown, the apparatus comprises'a tubular container 1 made from glass and formed at both-ends with tubular extensions 2 and 3 of reduced cross-section. The said extensions are connected by means of capillary glass tubes 4 and 5 with tubular containers 6 and 7. The wire, metal filament, metal band, or the like 8 is taken from a coil 9 and it is continuously passed through the container 6, the capillary tube 4, the container 1, the capillary tube 5 and the container 7, whereupon it is wound into a coil 10. The capillary tubes 4 and 5 are each formed with an enlarged portion 4' and 5' pronected by leads 13 and 14 fused through the wall of the container 1 to a source of electric energy. The container 1 is connected by a tube 15 comprising a cook 16 with an evacuating device such as a high vacuum pump 35. Both chambers 6 and 7 are connected by pipes 19 and 20 with a pipe 21 including a cook 22 and connected with an evacuating apparatus such as the pump 36. The pump is adapted to produce a higher vacuum than the pump 36,-and the pump 36 may cooperate with the pump 35 for producing a preliminary vacuum needed for producing the high vacuum within the pump 35. The pipes 15 and 21 are connected with each other by a pipe 24 including a cock 23, so that the container 1 may be connected with the pump 36 for rapidly producing a comparatively low vacuum within the container 1, and thereafter disconnected from .the pump 36 and connected with the pump 35 for producing the desired high vacuum. The chamhers 4 and 5' are connected by pipes 25'and 26 with pipes 19 and 20, and cocks 2'7 and 28 are provided which may be readily removed for supplying mercury to the chambers 4' and 5' before the operation of the apparatus is'start'ed.

It may be assumed that it is desired to coat a metal wire of high melting point, such for example as tungsten with zirconium. For this purpose an unstable zirconium compound such as zirconium tetra iodide is passed into the container 1" through tubular extensions 29 and 30, so that the said compound is collected on the bottom of the container 1. Thereafter the tubular extensions are closed by melting. The wire 8 taken from the coil 9 is passed through the apparatus and fixed to the spool 10, the cook 23 is opened, and the pump 36 is started so as to evacuate the chambers 1, 6

and 7. Thereafter the cock 23 is closed, and the operation of the pump 35 is continued, until the pressure within the container 1 is lower than that within the containers 6 and 7. Now also the cock 5 16 is closed, and the zirconium compound within the container 1 is vaporized, for example by means of a burner (as diagrammatically shown in Fig. 2) acting on the bottom of the containerl or by electrically heating the portion of the wire 8 located within the container 1. Now the wire 8 is continuously passed through the container 1 by turning the spool 10, and the portion thereof located between the blocks 11 and 121s continuously heated by the currentpassed therethrough by means of the leads 13 and 14, whereupon the vapour of metal compound is decomposed, and the metal is precipitated on the glowing part of the wire located between the contact blocks 11 and 12, thus producing a" coating of zirconium. Any traces of air which might pass through the stoppers 17' and 18 into the chambers 6 and 7 are immediately removed by the pump 36 connected with -the:fpipe 21, so .thatthe vacuum is maintained within the chambers-6 and 7.

' The pressure within the chambers 6 and 7 which are connected, during the operation of the apparatus, with the vacuum pump 36, should be slightly higher than the pressure within the container 1, and it may even be equal or substantially equal to the pressure within the said container.

In lieu of the rubber stoppers 17 and 18 capillary tubes filled with mercury may be provided, whichare similar in construction to the capillary tubes 4 and 5 and the chambers 4' and 5 thereof. This modification is shown in Fig. 2 in which the parts have received similar reference characters "as corresponding parts shown in Fig. 1. The container 1 is closed to the outer air by means of the mercury contained within the chamber 4 and a seal of mercury contained in a subsidiary chamber 4, the capillary tube 4 including a chamber 6' between the chambers 4' and 4 The chamber 6' is connected by the pipe 19 with the vacuum pump 36, and the chambers 41 and 4 are connected with the said pipe 19 by pipes 25 and 25 including cocks 27 and 27 During the operation of the apparatus the chamber 4 may be disconnected from the vacuum pump. Further, the container 1 may be connected with or disconnected from the pump 35 during the operation of the apparatus as may be necessary in the course of the operation.

In Fig. 3 I have shown another modification in which the container 1 is more effectively closed to the outer air by providing a plurality of seals and intermediate vacuum chambers at each side thereof. The construction of the apparatus is similar to the one described with reference to Fig. 1 and similar reference characters have been used to indicate corresponding parts. The capillary tubes 4 and 5 are provided each with two enlarged portions 4 and 5 filled with mercury, an enlarged portion 6 and 7 providing evacuated air chambers, and a chamber 6 7 closed by stoppers 17 and 18. The chambers 6 and 7 are connected by pipes 32 and 32' and a pipe 33 including a cock 34 with a vacuum pump 37, and the chambers 6 and 7 are connected by pipes 19 and 20, and a pipe 21 including a cock 22 with the vacuum pump 36. The pipe 21 is connected by the pipe 24 including the cock 23 with the pipe connecting the container 1 with the high vacuum pump 35, as has been described with reference to Fig. 1. The mercury chambers 4 4 and 5 5. are respectively connected by pipes 25, 37, 38 and 26 including cocks 27, 39, and 28 with the pipes 19, 32, 32' and 20. By means of the pump 37 a vacuum is produced in the chambers 6 and 7 so that the pressure within the said chambers is slightly higher than that within the container 1, and by means of the pump 36 a vacuum is produced in the chambers 6 and 7, so that the pressure within the said chambers is slightly higher than that within the chambers 6 and 7 Thus the pressure within the container 1 and the chambers connected therewith is gradually increased from the container 1 to the outer air, so that the admission of air to the container 1 is more effectively prevented. If the apparatus is to be used only for continuously glowing a wire the pipes 29 and 30 may be dispensed with.

I claim:

1. The herein described apparatus for the thermic treatment of elongated metal bodies in cluding means for heating said metal bodies, comprising a vacuum container having integral tubular extensions at opposite ends thereof for the passage of the said elongated bodies therethrough, spaced sealing means in each of said extensions through which said .elongated bodies are passed, and vacuumchambers intermediate said sealing means.

2. The herein described apparatus for the thermic treatment of elongated metal bodies including means for heating said metal bodies, comprising a vacuum container having tubular ex-.- tensions for the passage of the said elongated bodies therethrough, liquid sealing means in said extensions near the container, additional sealing means in said extensions spaced from said liquid sealing means and located at the outer sides thereof, and vacuum chambers intermediate the sealing means of said extensions.

3. The herein described apparatus for the thermic treatment of elongated metal bodies including means for heating said metal bodies, comprising a vacuum container having tubular extensions for the passage of the said elongated bodies therethrough, liquid sealing means in said extensions near the container, liquid sealing means in said extensions spaced from said firstnamed liquid sealing means and located at the outer sides thereof, and vacuum chambers intermediate the sealing means of said extensions.

4. The herein described apparatus for the thermic treatment of elongated metal bodies including means for heating said metal bodies, com-' prising a vacuum container having tubular extensions for the passage oi the said elongated bodies therethrough, spaced sealing means in each of said extensions through which said elongated bodies are passed, vacuum chambers intermediate said sealing means, means to evacuate said container, and means to evacuate said chambers to a' pressure higher than the pressure within said container.

5. The herein described apparatus for the thermic treatment of elongated metal bodies including means for heating said metal bodies, comprising a vacuum container having tubular extensions for the passage of the said elongated bodies therethrough, spaced sealing means in each of said extensions through which said elongated bodies are passed, vacuum chambers intermediate said sealing means, means to evacuate said container, and an evacuating de' vice connected with both chambers and adapted to evacuate the same toa pressure higher than that within the container.

6. The herein described apparatus for the thermic treatment of elongated metal bodies including means for heating said metal bodies, comprising a vacuum container having tubular extensions for the passage of the said elongated bodies therethrough, spaced sealing means in each of said extensions through whichv said elongated bodies are passed, vacuum chambers intermediate said sealing means, means to evacuate said container, an evacuating device connected with both chambers and adapted to evacuate the same to a pressure higher than that within the container, and means to connect and disconnect said container with said evacuating device.

g '7. The herein described apparatus for the thermic treatment of elongated metal bodies including means for heating said metal bodies,

7 comprising a vacuum container having tubular extensions for the passage of the said elongated bodies therethrough, spaced sealing means in each of said extensions through which said bodies therethrough, a plurality of sealing means in each of said extensions through which said elongated bodies are passed, and a vacuum chamber intermediate each 'pair of successive sealing means, and means to successively increase by gradual increments the pressure maintained within said container and vacuum chambers from the container to the outer end of said extensions.

9. The herein described apparatus for the thermic treatment of elongated metal bodies including means for heating said metal bodies, comprising a vacuum container having tubular extensions for the passage of the said elongated bodies therethrough, a plurality of spaced sealing means in each of said extensions through which said elongated bodies are passed, a vacuum chamber intermediate eachpair of successive sealing means, and means to successively increase by gradual increments the pressure maintained within said container and vacuum chambers from the container to the outer end ot said extensions, and evacuating devices each connected with corresponding vacuum chambers of both extensions.

10. The herein described apparatus for the thermic treatment of elongated metal bodies including means for heating said metal bodies, comprising a vacuum container having integral capillary extensions at opposite ends thereof for the passage of the said elongated bodies therethrough, spaced sealing means in each of said extensions through which said elongated bodies are passed, and vacuum chambers intermediate said sealing means.

KURT moans. as 

